Cesspit in Jerusalem shows how disease spread over 500 years ago

Jerusalem
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The excavation of a medieval cesspit in the Christian Quarter of the old city of Jerusalem is providing a window into how infectious diseases spread from Europe to the Middle East during the 15th century.

A team of researchers led by Dr. Piers Mitchell from Cambridge University's Division of Biological Anthropology used a combination of microscopy and biomolecular analysis (ELISA) to uncover parasite eggs from 12 "coprolites," or fossilized feces, and sediment from a medieval cesspit located north, and not too far from the Church of the Holy Sepulchre in the old city of Jerusalem.

The 500-year-old parasite eggs have provided clues into how infectious diseases spread between Europe and the Middle East during the 15th century. The cesspit isn't your run-of-the-mill hole in the ground. It had a vaulted roof, stone-built walls and two "entry-shutes," used for defecation on opposite sides of the structure.

The researchers found six species of intestinal parasites, including a large number of roundworm and whipworm eggs. These two parasites are spread through fecal contamination of food, and are believed to have been endemic to the region, dating back to the start of human evolution out of Africa.

Two additional parasites discovered, Entamoeba dysentery and the fish tapeworm, were common in medieval Northern Europe, yet relatively unknown or completely absent in the Middle East during the same period. The fish tapeworm was prevalent in Northern Europe because of the popularity of fish as a food. Fish was eaten raw, pickled or smoked, all of which don't kill the parasite.

According to Arabic texts written at that time, in inland Syrian cities, such as Jerusalem, fish was seldom if ever eaten. If any fish was to be consumed, it was fully cooked in accordance with local culinary customs. Of course, cooking thoroughly will kill the parasite. Italian pottery pieces were also found in the cesspit, giving further evidence of either trading or religious links between Jerusalem and Europe during the late 1400s.

Researchers surmise the cesspit was part of a large house owned by a wealthy merchant who traveled to Europe for trading purposes, probably picking up the parasites, or the cesspit could have been in a hostel, used by traveling merchants or those on pilgrimage to the city.

"While we can only suggest reasons as to why people made these journeys between northern Europe and Jerusalem's Christian quarter, it does seem they brought with them unsuspecting hitch-hikers in their intestines," said Dr. Mitchell. "The presence of the fish tapeworm -- which can reach ten metres long in humans, and coils around inside the intestine -- combined with the fragments of pottery made in Italy, most likely indicates that travelers from northern Europe used this latrine during a visit to Jerusalem," he said.

The really interesting finding in the coprolites was that one in particular had fish tapeworm eggs and Taenia parasite eggs, indicating pork or beef tapeworm had been consumed. Even though Islam was dominant during this time, the Mamluk Period (1250-1516 AD), pigs would have been consumed in the Christian quarter.

Dr. Mitchell says the health consequences of these parasites on the human population would have varied. Mitchell pointed out, "A light load of whipworm or roundworm would be likely to go unnoticed. A heavy load of these parasites in children, however, can lead to malnutrition, reduced intelligence, and stunted growth. Dysentery may cause diarrhea and abdominal cramps for a week or two and then settle, or it may cause death from dehydration and septicemia."

The research shows us how studying parasite eggs in ancient toilets can give us insight into human migration and the spread of disease. This research also shows us that while Jerusalem was an important destination for trading, unexpected travelers also came along for the ride.

This study was published in the [i]International Journal of Paleopathology[i], under the title: "Human intestinal parasites from a Mamluk Period cesspool in the Christian Quarter of Jerusalem: potential indicators for long distance travel in the 15th century AD."